The cellular fatty acid composition of 20 isolates of Neisseria gonorrhoeae and 21 isolates of N. meningitidis was examined by gas-liquid chromatography. Each isolate of the two species possessed similar fatty acid profiles which were characterized by five major acids, accounting for 80 to 85% of the total. The three most abundant acids in each species were palmitic, palmitoleic, and f3-hydroxylauric acids; lauric and myristic acids were the next most abundant. The presence of large amounts of f3-hydroxylauric acid (20% or greater) and the relative concentrations of the other four major acids appear to be useful markers for distinguishing N. gonorrhoeae and N. meningitidis fatty acids from those of other bacteria.

Amines produced by 31 strains of the Clostridium bifermentans and C. sordellii groups were compared by examining trifluoroaceticanhydride derivatives of basic chloroform extracts from spent cultural medium by gas–liquid chromatography (g.l.c.). All of the urease-positive strains (16) exhibited an amine profile consistent with that of C. sordellii. On the other hand, 12 of 15 urease-negative strains produced amine g.l.c. patterns like that of C. bifermentans, and three strains produced amine patterns identical with that of C. sordellii. The carbohydrate composition of some of the strains was determined by g.l.c. of trimethylsilyl derivatives of acid-digested formamide extracts of whole cells. Two of the three urease-negative strains with amine profiles like C. sordellii had a carbohydrate composition similar to that of C. sordellii, and the other strain had a carbohydrate profile more like that of C. bifermentans. One known strain of C. bifermentans had a carbohydrate profile with characteristics of both C. bifermentans and C. sordellii. The results of this study point out the variability of urease production by C. sordellii and the value of gas chromatography in differentiating this organism from C. bifermentans.

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Trimethylsilyl (TMS) derivatives prepared from whole-cell hydrolysates of 36 strains, representing 10 species of Clostridium were examined by gas-liquid chromatography (GLC). The TMS profile of each species contained a group of peaks which characterized the species. Variation among strains within a species was much lower than variation between species. Some of the closely related clostridia could be differentiated by comparing their TMS profiles. Strains of Clcstridium botulinum were distinguished from C. sporogenes on the basis of the ratio of two GLC peaks which corresponded to arabinose and glucose. A peak with a retention time identical to that of mannose was present in all C. bifermentans strains but was absent in those of C. sordellii. The genus Clostridium is composed of a very heterogeneous group of organisms which are gram-positive, anaerobic, catalase-negative, spore-forming rods. Some species of this genus fix atmospheric nitrogen, some are thermophilic, and others are pathogenic for man and animals. Various approaches have been used to study this diverse group of bacteria. Biochemical tests 55 C under a gentle stream of nitrogen. The residue was dissolved in 10 ml of hexane, and the volume was reduced to 0.25 ml under nitrogen. Reference sugar samples obtained from Sigma Chemical Co., St. Louis, Mo., were processed by the same procedure. 78

A tuberculin-active glycopeptide containing eight different amino acids and glucose was isolated from the protoplasm of Mycobacterium tuberculosis. A molecular weight of 4,000 to 5,000 was established by Sephadex gel filtration; other analyses showed a peptide to carbohydrate ratio of 9: 1. These observations suggest a tentative composition of 3 to 4 residues of glucose, 12 residues each of aspartic and glutamic acids, 3 residues each of lysine, glycine, and serine, and I residue each of arginine, threonine, and alanine.